The Siemens SENTRON 3VA2340-7HL42-0HB0 is a 4-pole molded case circuit breaker rated for 400 A continuous current at 40 °C, with a maximum breaking capacity of 330 kA at 240 V. That 330 kA figure at 240 V means it can safely interrupt a fault current up to that level without cascading upstream — critical for high-fault panels near large transformers or utility feeds. The breaker is designed for line protection and includes a shunt trip (STL) and two auxiliary switches (HP). No undervoltage release, no ground-fault monitoring, and no communication function are fitted on this variant.
Breaking capacity across voltage levels
The 3VA2340-7HL42-0HB0 delivers 242 kA at 415 V and 440 V, 187 kA at 500 V, and 7.5 kA at 690 V. The steep drop at 690 V is typical for this frame size — the arc energy at higher voltage limits the interruption capability. For a 400 V distribution board, the 242 kA rating gives generous headroom for most industrial SCCR requirements.
Thermal derating curve
The breaker holds its full 400 A rating from 40 °C up to 50 °C. Above that, it derates: 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If the panel ambient runs hot — say, a non-climate-controlled enclosure near a furnace line — factor the 55 °C or 60 °C row into your load calculation. Operating range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.
Mounting and integration
The breaker measures 248 mm high, 184 mm wide, and 110 mm deep. That 184 mm width on a 4-pole frame is standard for this SENTRON series — it will fit the same DIN-rail or panel-mount footprint as other 3VA2-frame breakers. The shunt trip (STL) and two auxiliary switches are factory-fitted; no field-add kit needed for those. Power loss is 96 W maximum at rated current — account for that in enclosure thermal calculations.